Merge branch 'for-4.13-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "The core updates improve error handling (mostly related to bios), with
  the usual incremental work on the GFP_NOFS (mis)use removal,
  refactoring or cleanups. Except the two top patches, all have been in
  for-next for an extensive amount of time.

  User visible changes:

   - statx support

   - quota override tunable

   - improved compression thresholds

   - obsoleted mount option alloc_start

  Core updates:

   - bio-related updates:
       - faster bio cloning
       - no allocation failures
       - preallocated flush bios

   - more kvzalloc use, memalloc_nofs protections, GFP_NOFS updates

   - prep work for btree_inode removal

   - dir-item validation

   - qgoup fixes and updates

   - cleanups:
       - removed unused struct members, unused code, refactoring
       - argument refactoring (fs_info/root, caller -> callee sink)
       - SEARCH_TREE ioctl docs"

* 'for-4.13-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (115 commits)
  btrfs: Remove false alert when fiemap range is smaller than on-disk extent
  btrfs: Don't clear SGID when inheriting ACLs
  btrfs: fix integer overflow in calc_reclaim_items_nr
  btrfs: scrub: fix target device intialization while setting up scrub context
  btrfs: qgroup: Fix qgroup reserved space underflow by only freeing reserved ranges
  btrfs: qgroup: Introduce extent changeset for qgroup reserve functions
  btrfs: qgroup: Fix qgroup reserved space underflow caused by buffered write and quotas being enabled
  btrfs: qgroup: Return actually freed bytes for qgroup release or free data
  btrfs: qgroup: Cleanup btrfs_qgroup_prepare_account_extents function
  btrfs: qgroup: Add quick exit for non-fs extents
  Btrfs: rework delayed ref total_bytes_pinned accounting
  Btrfs: return old and new total ref mods when adding delayed refs
  Btrfs: always account pinned bytes when dropping a tree block ref
  Btrfs: update total_bytes_pinned when pinning down extents
  Btrfs: make BUG_ON() in add_pinned_bytes() an ASSERT()
  Btrfs: make add_pinned_bytes() take an s64 num_bytes instead of u64
  btrfs: fix validation of XATTR_ITEM dir items
  btrfs: Verify dir_item in iterate_object_props
  btrfs: Check name_len before in btrfs_del_root_ref
  btrfs: Check name_len before reading btrfs_get_name
  ...

1 files changed, 15 insertions, 23 deletions

diff --git a/fs/btrfs/free-space-tree.c b/fs/btrfs/free-space-tree.c
index fc0bd8406758..a5e34de06c2f 100644
--- a/fs/btrfs/free-space-tree.c
+++ b/fs/btrfs/free-space-tree.c
@@ -17,7 +17,7 @@
  */
 
 #include <linux/kernel.h>
-#include <linux/vmalloc.h>
+#include <linux/sched/mm.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "locking.h"
@@ -153,21 +153,21 @@ static inline u32 free_space_bitmap_size(u64 size, u32 sectorsize)
 
 static u8 *alloc_bitmap(u32 bitmap_size)
 {
-	void *mem;
+	u8 *ret;
+	unsigned int nofs_flag;
 
 	/*
-	 * The allocation size varies, observed numbers were < 4K up to 16K.
-	 * Using vmalloc unconditionally would be too heavy, we'll try
-	 * contiguous allocations first.
+	 * GFP_NOFS doesn't work with kvmalloc(), but we really can't recurse
+	 * into the filesystem as the free space bitmap can be modified in the
+	 * critical section of a transaction commit.
+	 *
+	 * TODO: push the memalloc_nofs_{save,restore}() to the caller where we
+	 * know that recursion is unsafe.
 	 */
-	if  (bitmap_size <= PAGE_SIZE)
-		return kzalloc(bitmap_size, GFP_NOFS);
-
-	mem = kzalloc(bitmap_size, GFP_NOFS | __GFP_NOWARN);
-	if (mem)
-		return mem;
-
-	return __vmalloc(bitmap_size, GFP_NOFS | __GFP_ZERO, PAGE_KERNEL);
+	nofs_flag = memalloc_nofs_save();
+	ret = kvzalloc(bitmap_size, GFP_KERNEL);
+	memalloc_nofs_restore(nofs_flag);
+	return ret;
 }
 
 int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans,
@@ -1188,11 +1188,7 @@ int btrfs_create_free_space_tree(struct btrfs_fs_info *fs_info)
 	btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID);
 	clear_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags);
 
-	ret = btrfs_commit_transaction(trans);
-	if (ret)
-		return ret;
-
-	return 0;
+	return btrfs_commit_transaction(trans);
 
 abort:
 	clear_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags);
@@ -1277,11 +1273,7 @@ int btrfs_clear_free_space_tree(struct btrfs_fs_info *fs_info)
 	free_extent_buffer(free_space_root->commit_root);
 	kfree(free_space_root);
 
-	ret = btrfs_commit_transaction(trans);
-	if (ret)
-		return ret;
-
-	return 0;
+	return btrfs_commit_transaction(trans);
 
 abort:
 	btrfs_abort_transaction(trans, ret);